Support is requested for a Keystone Symposia meeting entitled Endoderm Lineages in Development and Disease, organized by Lori Sussel, Hans-Willem E. Snoeck, James M. Wells and Aaron M. Zorn. The meeting will be held in Keystone, Colorado from February 8-13, 2015. The endoderm gives rise to a vast array of highly specialized epithelial cell types lining the respiratory and gastrointestinal tracts and contributes to associated organs such as thyroid, thymus, lungs, liver, biliary system and pancreas. Basic studies of endoderm organ development and postnatal function have revealed the molecular basis of human congenital diseases, have identified new regenerative pathways, and have made it possible to grow endoderm organ tissues in vitro. While endoderm organs vary in their form and function, there are many shared mechanisms that govern the development and homeostasis of these organs. This Keystone Symposia meeting on Endoderm Lineages in Development and Disease will highlight recent advances in our understanding of endoderm organ development during embryogenesis and how this knowledge has led to successful efforts at generating human endoderm organ cells and tissues from pluripotent stem cells. The topic of this meeting fits perfectly with the NICHD's mission to elucidate the biochemical, molecular biological, genetic, and cellular mechanisms of embryonic development and determine how dysfunction of each of these processes lead to birth defects and disease.